Effect of Selenium-enriched Bean Sprout and Other Selenium Sources on Productivity and Selenium Concentration in Eggs of Laying Hens

Asian-Aust. J. Anim. Sci.

Vol. 22, No. 12 : 1661 -1666 December 2009

www.ajas.info

Effect of Selenium-enriched Bean Sprout and Other Selenium Sources on Productivity and Selenium Concentration in Eggs of Laying Hens

O. Chinrasri, P. Chantiratikul*1, W. Thosaikham1,P. Atiwetin2,S. Chumpawadee S.Saenthaweesukand A. Chantiratikul

*

* Corresponding Author: A. Chantiratikul. Tel: +66-87-173-8777, Fax: +66-43-742-823, E-mail: anut.c@msu.ac.th

1 Department of Chemistry and Center of Excellence for Innovation in Chemistry, (PERCH-CIC), Faculty of Science, Mahasarakham University, Kantarawichai, Maha Sarakham, 44150, Thailand.

2 Department of Agricultural Production Technology, Faculty of Technology, Mahasarakham University, Muang, Maha Sarakham, 44000, Thailand.

Received April 7, 2009; Accepted July 2, 2009

Animal

Feed

Resources

and

Animal

Nutrition

Research

Unit,

Faculty

of

Veterinary

and

Animal Sciences,

Mahasarakham

University,Muang,

Maha Sarakham,

44000, Thailand

ABSTRACT : The objective of this study was to determine the effect of Se-enriched bean sprout, Se-enriched yeast and sodium selenite on productivity, egg quality and egg Se concentrations in laying hens. Using a Completely Randomized Design, 144 Rohman laying hens at 71 weeks of age were divided into four groups. Each group consisted of four replicates and each replicate contained nine hens. The dietary treatments were T1: control diet, T2: control diet plus 0.3 mg Se/kg from sodium selenite, T3: control diet plus 0.3 mg Se/kg from Se-enriched yeast, T4: control diet plus 0.3 mg Se/kg from Se-enriched bean sprout. The results showed that there was no significant difference (p>0.05) in feed intake, egg production and egg quality among treatments. Selenium supplementation from Se- enriched yeast and Se-enriched bean sprout markedly increased (p<0.05) egg Se concentration as compared to the control and sodium selenite groups. The results indicated that Se-enriched bean sprout could be used as an alternative Se source in diets of laying hens. (Key Words : Se-enriched Plant, Organic Selenium, Egg Selenium Content, Laying Hens)

INTRODUCTION

Selenium (Se)

is

an essential component

of

several

major

metabolic

pathways, including thyroid

hormone metabolism, antioxidant defense system,

and

immune

function (Brown and Arthur,

2001). Interestingly, Se in selenoprotein

or

organicform hasbeen

found

tobeeffective in reduction of

cancer

incidence

in

animal models,

epidemiologic data and

more recent studies in humans

(Ganther, 1999;

Diwadkar-Navsariwala

and

Diamond, 2004). Animal

nutritionists have,

therefore, paid more attention to

supplementing Se

to enhance productive performance

and health of

animals

and

to produce

Se-

enrichedanimal

products to

increaseSestatus

of consumers.

Concerning the latter, it was

found that

organic Se can

readily accumulate into tissue protein

in

an unregulated

manner

(Thomson, 1998), resulting in

higher Se

concentration

in

animal products

when

compared to inorganic Se

as

reported

in

swine(Mahan

and

Parrett, 1996;

Mahanet

al., 1999; Olivera

etal.,

2005; Zhan

etal.,2007), beefcattle (Lawler et al., 2004), dairy cows (Juniper et al., 2005; Muniz-Naveiro et

al.,

2005), broilers (Payne and Sounthern, 2005;

Olivera

et

al.,

2005; Yoon et al., 2007), Japanese quails (Sahin et

al.,

2008)

and

laying

hens

(Payne

et al.,

2005;

Utterback et al.,

2005; Skrivan

et

al., 2006;Pan et

al.,

2007; Chantiratikul et al., 2008). Currently, enrichment

of

eggs

with Se

isbeingproducedin morethan 25 countries worldwide,deliveringapproximately 30-35 卩

_g Se or

50%

of

the recommended

daily

allowances (RDA)

with a

single

egg (Fisinin

et

al.,

2008). The Se-enriched eggs are

produced

using Se-enriched

yeast

as

a

major source

of

Se

for

laying

hens

at

a

level

of 0.3-0.5

mgSe/kg

in

feed(Fisinin et

al.,

2008). However,the

production process of

Se-enriched

yeast

requirescomplex

and

hightechnology (Suhajdaet

al., 2000;

Ouerdane

and

Mester, 2008). On the

other

hand, the

production of

Se-enriched

plants is

more

practical

(Sugihara et

al., 2004;

Tsuneyoshi et

al.,

2006).

Selenium

in

the forms

of

selenate

and

selenite

is

readily absorbed by the

plant and

converted metabolically

in

the

chloroplast

to organic Se compounds (Terry

et al.,

2000), which are

a

component

of

protein

in

plant tissues (Leustek

and

Saito, 1999; Tinggi, 2003). Numerous studies revealed

that

Se-enriched

plants

couldbe successfully

produced for

human

nutrition

usingedible

plants

suchasbroccoli sprouts (Finley et

al.,

2001),

green

onions

(Allium fistulosum)

(Kapolna

and Fodor,

2006),garlic (Tsuneyoshietal., 2006),

and

sprouts

of several

plants (Lintschinger et al.,

2000;

Sugihara et al., 2004). Additionally,

these

high-Se plants have anticarcinogenic activities (Finley et al.,

2001;

Yoshida et al., 2007). However, there

is

insufficient

information on utilization

of

Se-enriched plants in

terms of animal nutrition.

Jiakui and

Xiaolong (2004)

produced Se-

enrichedmalt

and

fed

it

to

laying

hens. They

found that

Se

from

sodium selenite

and

Se-enriched malt

insignificantly

deposited into

eggs and productivity of

the

hens

was not adversely

affected.

This result showed

that

Se-enriched plants couldbe

used as a Se

source inanimal

diets.

Sprouts are normally

utilized in

foodstuffs

of Asian

people

and

the Se species

in

Se-enriched sprouts is mostly exhibited

in

organic

form

(Sugiharaetal., 2004). Presently,theeffect of Se-enriched sprout

on

laying hens

has never been studied.

Hence, thisstudywasdesignedto comparethe effect

of Se-

enriched

bean

sprout

with

other Se sources onproductivity

and

Se

concentration

in eggs

of laying hens.

MATERIALS AND METHODS

Se-enriched

bean

sproutwas

produced

by cultivation

of

mung

bean seeds

(Vigna radiata)

in

opaque plastic containers (22x36x

11 cm),

containing

cleaned sand after

soakingthe seeds in

distilled

water

for

8

h.

These cultivated seeds were applied

with

400 ml

distilled water

containing 90

mg Se from

sodium selenate/L.

The container

was fully covered by

a

black plastic bag. The

bean

sprouts were harvested

after cultivation

in thedark

for

3

days,

thoroughly

washed

with deionised

water,

dried at 50°

C

to constant

weight and

ground. Prior to

preparation of

dietary treatments, Se-enriched

bean

sprout

and

Se-enriched

yeast

(Alkosel®

,

Lallemand,Inc., Canada)were analysed

for

total Sebyinductively coupled plasma-mass spectrometer

(ICP-

MS Model Elan-e, Perkin-Elmer SCIEX, USA) according to Joaquim etal. (1997).

The experiment was conducted in evaporative system housing

with

an

internal

temperature set at 24°

C.

Internal

lights

were oncontinuously.

A

total of 144

Rohman laying

hens,

71

weeks old, wererandomly

allocated

into

4

groups;

eachgroup contained 4 replicates

with

9

hens per

replicate

and

was

placed

inwire cages, three

hens per cage.

Feeders between the different cages were separated by plastic sheetingtoavoidcross-contamination

of

dietary treatments.

Water

wasfreely availablefromnippledrinkers

in

thecages.

All hens

had been

molted

and

returned to

typical

egg

production

levels

before

the

start of

the experiment. The control diet

(Table 1)

was

formulated

to meet the nutrient requirements

of laying

hens according to NRC

(1994),

without

Se

supplementation. Selenium fromsodiumselenite, Se-enriched yeast,

and

Se-enriched

bean

sprout was added

to

thecontroldietin

a concentration of 0.3 mg

Se/kg,which

is

commercially used in producing Se-enriched

eggs

(Fisininet

al.,

2008). Thehens receivedthecontrol

diet for a

week

prior

to the beginning

of

the experiment

and

were

fed

dietary treatments ad libitum during

6 experimental

weeks.

Feed

consumption

and egg production

were

recorded daily.

The

experimental

dietswererandomly collectedatthe

end of

each week,

pooled

by treatment,

and

analysed

for

chemicalcomposition (AOAC, 1999)

and Se content.

Feed

conversion rate

was calculated

as

kilograms

of

feed consumed

per

kilogram of

eggs. Eight

eggs from each experimental group were sampled weekly (two eggs

per

replicate).

Four

collected eggs in

each

treatment were

measured for egg

weight, Haugh units,

and

eggshell thickness. Haugh units

and eggshell

thickness were

measured

using an albumen height gauge (TSS-QCD instrument, England)

and

a

micrometer

(395-541-30 BMD- 25DM, Mitutoya, Japan), respectively.

1 Sodiumselenite, Se-enriched yeast andSe-enrichedbean sprout were mixed incorn and added tothe dietto achieve the treatment levels.

2 Vitamin-mineral premix provide (per kg diet): 10,000 IU vitamin A, 2,000 IU vitamin D3, 11 mg vitamin E, 1.5 mg vitamin K3, 1.5 mg thiamin, 4 mg riboflavin, 10 mg pantothenic acid, 0.4 folic acid, 4mg pyridoxine, 22 mg niacin, 0.4 mg cobalamin, 0.1mg biotin, 60 mgFe, 70 mg Mn, 50 mg Zn, 8 mg Cu, 0.5mg Co, 0.7 mg I.

3 Calculatedvalue.

Table 1. Feed ingredients and chemical composition of control diet1

Feed ingredients % DM

Corn 59.00

Rice bran 4.25

Soybean meal (44% CP) 16.00

Fish meal 6.36

Soybean oil 2.78

Dicalcium phosphate 1.65

Oyster shell meal 8.44

DL-methionine 0.15

Salt 1.12

Vitamin-mineral premix2 0.25

Analyzed chemical composition

Dry matter 83.84

Crude protein 16.41

Ether extract 1.39

Crude fiber 1.62

Ash 16.01

ME3 (kcal/kg) 2,950

Table 2. Selenium concentrations in selenium-enriched yeast, selenium-enriched bean sprout and dietary treatments

Items Selenium (mg/kg)

Selenium-enriched yeast Selenium-enriched bean sprout Control diet

Control diet plus 0.3 mg Se/kg from sodium selenite Control diet plus 0.3 mg Se/kg from selenium yeast Control diet plus 0.3 mg Se/kg from selenium bean sprout

2,117.08 223.45 0.40 0.78 0.72 0.82

Whole

egg Se concentration

was determined in two eggs

collected

weekly

in each

treatment. The liquid eggs were weighed, homogenized well, dried at 65°

C for

12 h

and ground

before determining

Se

concentration.

Egg yolk and egg albumin of another

two eggs were separated, dried at65°

C for

12 h

and ground for

Se analysis. Approximately

0.5 g of ground

dietarytreatments, whole egg,

egg

yolkand

egg

albuminweredigestedin

a mixture of 1

ml

HNO

3

and

9

ml

deionized water until the solution was

clear.

Subsequently, thesolutionwas diluted

with deionized water

to

a final

volume

of

25

ml. Se

was determined by inductively coupled plasma-mass spectrometer (ICP-MS Model Elan-e,

Perkin-Elmer

SCIEX,

USA)

according to

Joaquim

et

al.

(1997).

Statisticalanalysis

The

data

on feed intake, feed

conversion

rate, egg production,

egg

quality

and Se

concentrations

in

whole

egg, egg yolk and egg albumin

were analyzed by one-way ANOVA (SAS, 1996). The differences among means

for each

parameterwere comparedby

Duncan

’

s

NewMultiple

Range

Test (Steel

and Torrie,

1980). Differences were consideredsignificantatp<0.05.

RESULTS

Se-enriched yeast

and

Se-enriched

bean

sprout contained 2,117.08

and

223.45

mg

Se/kg,

respectively.

The actual concentrations

of

Se in the control

diet

and diets supplementedwith

0.3

mg Se/kgfromsodiumselenite,

Se-

enrichedyeast

and Se-enriched

beansprout were 0.4,

0.78,

0.72

and

0.82 mg/kg,respectively (Table2).

The results obviously demonstrated

that

feed

intake,

feed

conversion rate/kg

eggs,

egg production

and

egg

quality

of laying

henswere notnegatively altered (p<0.05) by

Se

supplementalsources

(Table 3).

Seleniumconcentrationsinwhole

egg, egg

yolk

and

egg

albumin increased

(p<0.05)

with increasing

dietary Se supplementation. Whole

egg Se

concentrations

of

laying hens

fed Se

supplementaldiets

from

Se-enriched

yeast

and Se-enriched bean sprout were

not

significantly different

(p>0.05), but higher

(p<0.05)

than

those

of hens fed

the control

diet and

the

Se supplemental

diet from

sodium

selenite. Selenium

from

Se-enriched bean sprout

dramatically

accumulated(p<0.05)

in egg

yolk,however Se

from

Se-enriched yeast significantly

increased

(p<0.05)

Se accumulation in egg

albumin

when

compared to other sources

of

Se

(Table

4).

Whole

egg Se contents of

hens

fed

Se supplemental diets

from

Se-enriched yeast

and

Se-enriched bean sprout were

similar

(p>0.05),

but

significantly higher (p<0.05)

than

those

of

hens fedthe control

diet and Se

supplemental diet

from

sodiumselenite

(Table

4).

DISCUSSION

The results

of

feed intake, feed efficiency, egg

production and egg

quality in the current experiment

are

consistent

with other

studies comparing the effect

of

inorganic Se

and

Se-enriched

yeast on

layinghens (Payneet al., 2005;

Utterback

et

al.,

2005; Chantiratikul et al.,2008).

Furthermore, Jiakui

and

Xiaolong (2004)

found that

the

productivity of

hens was not

influenced

by adding 0.51 mgSe/kg

diet

from sodiumselenite

or

Se-malt. The dietary

Table 3. Effect of selenium sources on performance, egg production and egg quality of laying hens (n = 24)1

Items C SS SY SBS SEM

Feed intake (g/d) 105.08 107.13 102.98 105.45 1.35

Feed conversion rate/kg eggs 1.86 1.95 1.92 1.90 0.03

Egg production (%) 75.60 73.08 70.43 75.40 1.76

Egg weight (g) 65.69 64.89 64.15 65.25 0.40

Haugh units (HU) 74.50 78.17 74.58 70.71 1.21

Eggshell thickness (mm) 0.33 0.33 0.34 0.33 0.004

1 C = Control diet,SS =Controldiet plus0.3 mg Se/kg fromsodium selenite, SY = Control diet plus 0.3mgSe/kgfrom selenium yeast, SBS = Control dietplus 0.3 mg Se/kg from seleniumbean sprout.

Table 4. Effect of selenium sources on selenium concentrations (mg/kg) in whole egg, egg yolk and egg albumin and selenium content in whole egg (卩 g/egg) of laying hens (n = 12)1

Items C SS SY SBS SEM

Se concentration in whole egg 1.31c 2.28b 3.28a 2.90a 0.13

Se concentration in egg yolk 1.25c 2.57b 2.60b 2.97a 0.09

Se concentration in egg albumin 0.44d 0.67c 1.79a 0.98b 0.07

Se content in whole egg 17.60c 29.47b 42.61a 39.18a 1.78

이3, c Means withinsame row with differentsuperscripts differ (p<0.05).

1 C = Control diet, SS = Control diet plus 0.3 mgSe/kgfromsodium selenite, SY =Controldiet plus0.3 mg Se/kgfrom selenium yeast, SBS = Control dietplus 0.3 mg Se/kg from selenium bean sprout.

Se requirement

and Se

toxicity

of

laying hens have

been

recommended at

0.05 and 10 mg

Se/kg

diet,

respectively

(NRC,

1994).

Ort and

Latshaw (1978) revealedthata 9mg Se/kg

diet

supplemented from sodiumselenite resulted

in a reduction

of

egg weight and egg production

of laying

hens.

Although,

thetoxicity

of

organic Se in laying hens

has

not been directly reported,

diets

containing

20

mg Se/kg in selenomethionine form

caused

decreases in food consumption

and growth of mallard

duckling (Heinz etal., 1988). Thepresent

results

indicatedthatsupplementationof 0.3 mg Se/kg

diet

from Se-enriched bean sprout can be safely applied

for

laying hens

without

diminishing productivity.

Egg Se concentration is

directlycorrelatedtodietary Se supplementation

and

form

of

dietary

Se

(Golubkina

and

Papazyan, 2006). Consequently,

egg Se

concentration increased with increasing

Se supplemental

level,

and

organic Se was moreeffective

for deposition

intoeggs than inorganic

Se

(Payneetal.,

2005;

Skrivanet

al.,

2006;Pan et

al.,

2007; Chantiratikul et

al.,

2008).

The

present results similarly reflected

that

Se

from

Se-enriched yeast

and Se-

enriched bean

sprout had

higher accumulation into the whole

egg of laying

hens

than Se

from sodium selenite

(Table

4). Se-enriched

yeast

contains Se mainly in the organic form

of selenomethionine (Whanger,

2002).

Although,

Se-enrichedbean

sprout

used

in

thepresentstudy was

not

determined

for Se

speciation,

previous

studies (Finley et

al.,

2001; Sugihara etal., 2004) reported

that

the

main

Se species

in

the sproutswas Se-methyselenocysteine, which is

a common

metabolite

from

selenate or selenite in Se-enriched vegetables.

The

difference

in

major forms of organic Se

in

yeast

and bean sprout

wasprobablyconfirmed by Se

accumulation in egg yolk and egg albumin

(Table4), indicating the

different

metabolic pathways

of

Se constituents in Se-enriched yeast

and

Se-enriched bean sprout. Absorbed selenomethionine can

be

incorporated non-specifically into proteins

in

place

of

methionine and also can be converted to selenocysteine that can be degraded to selenide. Similarly, methyselenol, which

is a product of

Se-methyselenocysteine catabolism, can be converted to selenide. The selenide finally enters the

Se-

protein synthetic metabolism (Comb, 2001). Additionally,

selenomethionine can be produced by inorganic Se

in

animals,

but its

pathway

is unknown (Whanger,

2002). The

Se

metabolism pathway obviously

indicates

that both organic

and

inorganic Secanbeconvertedtoselenoprotein.

However, organic

Se

ismore effective

than

inorganic

Se in

this respect (Thomson, 1998). Most published reports studied the

effect of

organic Se inyeast

or

inthe form

of

selenomethionine

and

inorganic

Se on Se concentration in

eggs

of

laying hens

(Paton et

al., 2002; Payne et al., 2005;

Panet

al.,

2007;Chantiratikuletal., 2008).Only,

Jaikui

and

Xiaolong

(2004)

found

that,

although

Se

in

Se-maltwas an organic form, Se

deposition in

whole

egg of hens

fed

Se- malt or

sodium selenite were

not

different (p>0.05). They concluded that Se

in Se-malt

was predominantly

not in

the form

of

selenomethionine. Additionally, Se

in

Se-enriched Chlorella

(Skrivan

et

al.,

2006)

and spent compost of Se-

enriched mushrooms (Lee et

al.,

2006) was actively bio- availableto

egg and

muscle

of

beefsteers,

respectively.

The aforementionedpromisingresults demonstratedthat various forms

of

Se can be supplemented

in

diets

of

animals.

Therefore, Se-enriched

plants

should be further

studied in terms of

animalnutrition.

Generally, Se-enriched yeast is

widely

used

in Se-

enriched

egg

production, containing 30 to 35 卩g Se/egg (Fisinin et

al.,

2008).

Egg

Se content

of

laying hens

fed

Se from yeast

and

beansprout

in

thepresentstudy ranged

from

39.18

to 42.61

卩

g

Se/egg

(Table 4),

which

is higher

than that

of

commercial

Se-egg.

Thiswasprobably due

to higher

dietary

Se concentration

(0.72 to

0.82 mg

Se/kg)

when

compared to that

in

diets

(0.3

to

0.5 mg

Se/kg)

for

Se-egg

production

(Fisininetal., 2008). The resultsclearly indicate that Se-enriched bean sprout was comparable to

Se-

enriched

yeast in

producing Se-enrichedegg.

CONCLUSION

Se-enrichedbean sprout, Se-enriched

yeast and

sodium selenite did

not

alter (p>0.05) feed intake,

egg production

and egg

quality

of

laying hens.

Egg

Se concentrations

of

laying hens

fed Se supplemental

diets

from

Se-enriched bean

sprout and

Se-enriched yeast were

not

different

(p>0.05).

ACKNOWLEDGMENTS

Mahasarakham University funded

this study

in budget

fiscal

year 2008.

The authors

thank Mr. K.

Ruechai,

Ms.

P.

Roonsamrong,

Ms.

P. Suthamwong

and Mr.

W. Jeebjoho

for

sprout

cultivation and data

collections. The

experimental

henswere supportedby

Mahasarakham University farm.

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